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No full textAbstract Definition A Zero-Knowledge Proof is an interactive protocol which allows one party (the prover) to prove a statement (S) to another party (the verifier) without revealing anything beyond the truth of S. If S is true then the prover should always be able to convince the verifier that the statement is true without revealing anything else. For example
A Novel Porphyrin-Based Photocatalytic System for Terpenoids Production from (R)-(+)-Limonene
No full textA porphyrin-based photoexcited system has been revealed to be an efficient catalyst for D-limonene biotransformation under mild conditions and using molecular oxygen or/and H 2 O 2 as oxidants. The influence of the oxidant, the wavelength of visible light, and the photoexcitation time on the catalytic system were studied for limonene oxidation with 5,10,15,20-tetraphenylporphyrin (H 2 TPP) as a catalyst. This porphyrin-catalyzed oxidation of limonene to three main products identified as carvone, an unknown product with a verbenone-like mass spectrum (1), and a (1S,4R)-p-mentha-2,8-diene 1-hydroperoxide (2). The highest conversion yield of these products was achieved at a very high molar ratio of H 2 TPP to limonene. The dependence of the biotransformation yield on the kind of solvent with different acceptor/donor electron properties was also investigated. Ethyl alcohol proved to be the best among the considered additives used for the reaction. Limonene photooxidation was not significantly dependent on wavelengths of visible light. It was concluded by UV-vis experiments that the reaction proceeds via a free-radical or/and molecular mechanism. Additional evidence for its radical nature was obtained from reactivity investigations. Maximal yield of carvone was obtained in the medium containing 90% of the substrate, within the period of 18 to 36 h of exposition to sunlight
Neuropsychopharmacology advance online publication
No full textImpairments in social cognition are common in schizophrenia and predict poor functional outcome. The purpose of this proof-of-concept randomized, parallel group clinical trial was to assess whether intranasal oxytocin (OT), given before social cognitive training, enhances learning of social cognitive skills. Twenty seven male outpatients with schizophrenia participated in a 6-week (12 session) training on social cognitive skills. Training focused on three domains: facial affect recognition, social perception, and empathy. Subjects were randomly assigned (double blind) to receive either intranasal OTor placebo 30 min before each session. Participants did not receive OT between sessions or on the day of assessments. We evaluated scores on social-cognition measures, as well as clinical symptoms and neurocognition, at baseline, 1 week following the final training session, and 1 month later. Our prespecified primary outcome measure was a social-cognition composite score comprised of five individual measures. There were main effects of time (indicating improvement across the combined-treatment groups) on the social-cognition composite score at both 1 week and 1 month following completion of training. Subjects receiving OT demonstrated significantly greater improvements in empathic accuracy than those receiving placebo at both posttreatment and 1 month follow up. There were no OT-related effects for the other social cognitive tests, clinical symptoms, or neurocognition. This study provides initial support for the idea that OT enhances the effectiveness of training when administered shortly before social cognitive training sessions. The effects were most pronounced on empathic accuracy, a high-level social cognitive process that is not easily improved in current social cognitive remediation programs
Greek Physicians' Perceptions on Generic Drugs in the Era of Austerity
No full textproperly cited. Purpose. To assess the beliefs and preferences of Greek physicians, regarding generic drugs, in the years of financial crisis. Setting. Multicentered, nationwide survey. Material and Methods. A custom questionnaire based on former similar studies was developed and administered to Greek physicians. The variable "perception on generics" was constructed after an exploratory study and the instrument was validated by conventional and Rasch analysis methods. 22 items formed 5 subscales that constructed the variable in question. Results. 908 physicians successfully participated in the study (response rate: 80%). Mean total scores to the instrument were 60.63 ± 12.12 for men and significantly less (58.24 ± 11.73) for women (p = 0.04). Greek physicians were not persuaded on the potential economic gain (45.79 ± 10.53); moreover they identified that Greek authorities cannot address the increased pharmacovigilance mandates. Physicians working in Athens and those working in surgical units demonstrated significantly worse scores than their colleagues from the rest of Greece and those working in Internal Medicine wards (p = 0.03). Conclusion. Our results suggest an overall poor acceptance of the national initiative on generic drugs by Greek physicians. This trial is registered with Clinicaltrials.gov identifier: NCT01855802
SiPM response to long and intense light pulses
No full texta b s t r a c t Recently Silicon Photomultipliers (SiPMs) have become well recognized as the detector of choice for various applications which demand good photon number resolution and time resolution of short weak light pulses in the nanosecond time scale. In the case of longer and more intensive light pulses, SiPM performance gradually degrades due to dark noise, afterpulsing, and non-instant cell recovering. Nevertheless, SiPM benefits are expected to overbalance their drawbacks in applications such as X-ray cargo inspection using Scintillation-Cherenkov detectors and accelerator beam loss monitoring with Cherenkov fibres, where light pulses of a microsecond time scale have to be detected with good amplitude and timing resolution in a wide dynamic range of 1
Centroiding and Point Response Function Measurements of the Mirror/Detector Combination for the X-ray Telescope of the Swift Gamma Ray Burst Explorer
No full textABSTRACT The essential optical components of the Swft X-ray Telescope (XRT) are already developed items. They are: the flight spare x-ray mirror from the JET-X/Spectrum-X program and a MOS CCD (CCD22) of the type currently operating in orbit as part of the EPIC focal plane camera on XMM-Newton' . The JET-X mirrors were first calibrated at the Max Plank Institute for Extraterrestrial Physics' (MPE) Panter facility, Garching, Germany in 19962, 3 Halfenergy widths (HEW) of 16 arc seconds at 1 .5 keV were confirmed for the two flight mirrors and the flight spare. The calibration ofthe flight spare was repeated at Panter in July 2000 in order to establish whether any changes had occurred during the four years that the mirror had been in storage at the OAB, Milan, Italy. The results reported in this paper, confirm that the resolution of the JET-X mirrors has remained stable over this storage period. In an extension ofthis test program, the flight spare EPIC camera was installed at the focus ofthe JET-X mirror to simulate the optical system of the Swft X-ray telescope. On-axis and off-axis point spread Ilinctions (PSFs) were measured and calibration data sets were used to obtain centroid positions of X-ray point sources. The results confirmed Swift's ability to determine the centroid positions of sources at lOOmCrab brightness to better than 1 arc second and provided a calibration of the centroiding process as a function of source flux and off axis angle. The presence of background events in the image frame introduced errors in the centroiding process, making the choice of centroiding algorithm important. Algorithm performance and the trade-off between processing speed and centroiding accuracy were investigated
Lattice Model for Metal Ammonia Solutions
No full textWe study metal ammonia solutions using a generalized Kimball-Falicov model. The lattice model contains a fluid-fluid interaction term and an electron-fluid interaction with a hard core and an attractive tail. We derive the phase diagram using a strong-coupling mean field theory based on the slave boson approach to the Hubbard model. The attractive force favors the homogeneous phase and a regime where electrons localize in cavities devoid of fluid particles over phase separation. The Gaussian fluctuations suggest the existence of bicontinuous channels percolating through the system. Comparisons with experiments and computer simulations are presented. [S0031-9007(97) PACS numbers: 71.22.+i, 61.25.Mv, 71.10.Fd, 71.30.+h Metal ammonia solutions exhibit a metal-insulator transition (MIT) and a variety of thermodynamic phases Our model is a modified Kimball-Falicov model ͑c ist , c ist ͒ are Grassmann (fermionic) fields for site i, spin s, and Euclidean time index t, n i 0, 1 describes the blocker occupancy of site i, and l i and j i are generating fields. y ij and w ij . 0 are fermion-blocker and blocker-blocker attractive forces, respectively. m e and m b are the chemical potentials, and b h 1. We apply the constraint that blockers and fermions cannot simultaneously occupy the same site. This onsite exclusion and the attractive interaction y ij compete with each other. The model can be thought of as the quantum analog of a classical lattice model [9] that features short-ranged, competing forces and describes the lamella and bicontinuous microemulsion phases of oilwater-surfactant mixtures The exclusion constraint is difficult to implement in practice except in special cases where L i ln͓1 1 e m e ͑12a͒2l i ͔ and a is arbitrary. When n i 1, ͑c ist , c ist ͒ describe auxillary fermions that do not exhibit hopping, whose free energy contribution L i per spin has been subtracted out in Eq. (2). ͑S o 1 S aux ͒ now has 2N unconstrained fermionic and N blocker degrees of freedom which can be decoupled using the Hubbard-Stratonovich transfor
Structural decomposition of the chemical shielding tensor: Contributions to the asymmetry, anisotropy, and orientation
Get PDFThe nine elements of chemical shielding tensors contain important information about local structure, but the extraction of that information is difficult. Here we explore a semiempirical method that has the potential for providing relatively accessible structural correlations. The approach entails approximating the field-induced electron current density as entirely perpendicular to the applied field. This has two interesting consequences. ͑1͒ The resulting shielding tensor is perfectly symmetric. Thus, asymmetry in a shielding tensor is an indication of current density that is not orthogonal to the applied field. ͑2͒ The orientation dependence of the chemical shielding at a point of interest is related explicitly to the isotropic average of the chemical shielding at every point in the surrounding region. This suggests a relatively simple relationship between the orientation dependence of the chemical shielding and the molecular structure. Good correlation with experimental tensors is obtained with just one or two adjustable parameters in several series of compounds, including silicates, phosphates, hydrogen bonds, carboxyls, and amides. As expected, the results indicate that for a given center, the contribution to the shielding anisotropy that is associated with each bonded neighbor increases as the number of electrons at either the center or the neighbors increases
MINIMIZING CARBON DIOXIDE EMISSION BY ROUTING TO BE FERTILIZER
No full textAbstract The acceleration in carbondioxide emissions since 2000 is more than a 3% increase per year (more than 2 ppm per year) from 1.1% per year during the 1990s. Carbon dioxide is one of greenhouse gas which contribute 9-26% to global warmin